To fix a turntable, first identify the exact problem, such as the turntable not spinning, the turntable spinning faster than it should or the tonearm not dropping on the turntable. The turntable can also produce crackling sounds or no sound at all.
If the turntable spins faster than the record's speed, remove the upper plate, and inspect the motor. If the drive is slipping, align it. If the turntable doesn't spin, the motor needs replacement. Additionally, check for loose wiring.
If you hear cracking sounds or any unusual sounds, use an antistatic cloth to clean dust off the turntable. Additionally, check whether the tonearm is properly balanced. If the turntable doesn't produce any sound, replace the needle. If the problem persists, replace the stylus, too.
If the tonearm doesn't drop on the turntable or suddenly malfunctions when playing a record, hold the Stop button, manually rotate the turntable by 90 degrees, and then release the Stop button. This should reset the tonearm. If problems with the tonearm arise regularly, clean the turntable from time to time.
If the turntable stops revolving on its own, the drive is faulty. If the turntable is using a belt drive, replace the drive. On the other hand, if it's using a direct drive, you have no option but to get another turntable.